TY - JOUR
T1 - Big defensin from the scallop Argopecten purpuratus ApBD1 is an antimicrobial peptide which entraps bacteria through nanonets formation
AU - Stambuk, Felipe
AU - Ojeda, Claudia
AU - Machado Matos, Gabriel
AU - Rosa, Rafael Diego
AU - Mercado, Luis
AU - Schmitt, Paulina
N1 - Funding Information:
This study was supported by the Chilean National Fund for Scientific and Technological Development, FONDECYT Grants # 1200129 and # 11150009 and by the Brazilian funding agency CNPq (Grants # 406530/2016-5 and # 307032/2018-3 ). GMM was supported by scholarships provided by FAPESC and CAPES (PrInt 41/2017).
Publisher Copyright:
© 2021 Elsevier Ltd
PY - 2021/12
Y1 - 2021/12
N2 - Big defensins is a large family of antimicrobial peptides found in restricted groups of invertebrates, in particular mollusks where they have highly diversified. Big defensins are composed of a highly hydrophobic N-terminal region and a C-terminal region containing six cysteine residues whose arrangement is identical to that of vertebrate β-defensins. They have been shown to be active against both Gram-positive and Gram-negative bacteria and fungi. Antimicrobial aggregates called nanonets entrapping and killing bacteria have been recently described for the hydrophobic N-terminal region of the Cg-BigDef1 from the oyster Crassostrea gigas. To determine whether nanonets formation is a conserved trait of mollusk big defensins, we assessed the potential entrapping of bacteria through nanonets of the big defensin from the scallop Argopecten purpuratus, ApBD1. Recombinant ApBD1 was produced with a thrombin-cleavable N-terminal His6 tag, followed by the mature peptide carrying a mutation of the last cysteine residue of the C-terminal region by and arginine, named rApBD1(C87R). This mutation did not apparently affect the three-dimensional structure and the biological properties of rApBD1(C87R), as evidenced by in silico modeling and in vitro antimicrobial assays. Strong immune staining of rApBD1(C87R) in numerous areas surrounding bacteria was observed by confocal microscopy, suggesting that rApBD1(C87R) entraps bacteria in peptide aggregates similar to those reported to the oyster big defensin. This study suggests the conservation of bactericidal activity and nanonet formation across big defensins from bivalve mollusks.
AB - Big defensins is a large family of antimicrobial peptides found in restricted groups of invertebrates, in particular mollusks where they have highly diversified. Big defensins are composed of a highly hydrophobic N-terminal region and a C-terminal region containing six cysteine residues whose arrangement is identical to that of vertebrate β-defensins. They have been shown to be active against both Gram-positive and Gram-negative bacteria and fungi. Antimicrobial aggregates called nanonets entrapping and killing bacteria have been recently described for the hydrophobic N-terminal region of the Cg-BigDef1 from the oyster Crassostrea gigas. To determine whether nanonets formation is a conserved trait of mollusk big defensins, we assessed the potential entrapping of bacteria through nanonets of the big defensin from the scallop Argopecten purpuratus, ApBD1. Recombinant ApBD1 was produced with a thrombin-cleavable N-terminal His6 tag, followed by the mature peptide carrying a mutation of the last cysteine residue of the C-terminal region by and arginine, named rApBD1(C87R). This mutation did not apparently affect the three-dimensional structure and the biological properties of rApBD1(C87R), as evidenced by in silico modeling and in vitro antimicrobial assays. Strong immune staining of rApBD1(C87R) in numerous areas surrounding bacteria was observed by confocal microscopy, suggesting that rApBD1(C87R) entraps bacteria in peptide aggregates similar to those reported to the oyster big defensin. This study suggests the conservation of bactericidal activity and nanonet formation across big defensins from bivalve mollusks.
KW - Antimicrobial peptide
KW - Big defensins
KW - Host defense peptides
KW - Mollusk
KW - Nanonets
KW - Scallop immunity
UR - http://www.scopus.com/inward/record.url?scp=85117881548&partnerID=8YFLogxK
U2 - 10.1016/j.fsi.2021.10.037
DO - 10.1016/j.fsi.2021.10.037
M3 - Article
AN - SCOPUS:85117881548
VL - 119
SP - 456
EP - 461
JO - Fish and Shellfish Immunology
JF - Fish and Shellfish Immunology
SN - 1050-4648
ER -